unit Unit3;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, Grids, DBGrids, StdCtrls, jpeg, ExtCtrls;

type
  TForm3 = class(TForm)
    Button1: TButton;
    Button2: TButton;
    GroupBox1: TGroupBox;
    Button3: TButton;
    Button4: TButton;
    Label1: TLabel;
    Label2: TLabel;
    Edit1: TEdit;
    Edit2: TEdit;
    GroupBox2: TGroupBox;
    Label3: TLabel;
    Edit3: TEdit;
    Button5: TButton;
    Button6: TButton;
    Button7: TButton;
    DBGrid1: TDBGrid;
    Image1: TImage;
    procedure Button6Click(Sender: TObject);
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
    procedure Button5Click(Sender: TObject);
    procedure Button7Click(Sender: TObject);
    procedure Button4Click(Sender: TObject);
    procedure Button3Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form3: TForm3;
var
  a:integer=1;
  lentdate:string;
  backdate:string;
  sql:string;

implementation

uses dem;

{$R *.dfm}

procedure TForm3.Button6Click(Sender: TObject);
begin
close;
end;

procedure TForm3.Button1Click(Sender: TObject);
begin
a:=1;
GroupBox1.Caption:='圖書借閱';
groupbox1.Color:=clOlive;
end;

procedure TForm3.Button2Click(Sender: TObject);
begin
edit1.Clear;
edit2.Clear;
a:=2;
groupbox1.Caption:='圖書歸還';
groupbox1.Color:=clLime;
end;

procedure TForm3.Button5Click(Sender: TObject);
var sno:string;
begin
sno:=trim(edit1.Text);
dm.lent.Active:=false;
dm.lent.CommandText:='select * from lent where sno='''+edit3.Text+'''';
dm.lent.active:=true;
dm.lent.requery;

end;

procedure TForm3.Button7Click(Sender: TObject);
begin
edit3.Clear;
end;

procedure TForm3.Button4Click(Sender: TObject);
begin
edit1.Clear;
edit2.Clear;
end;

procedure TForm3.Button3Click(Sender: TObject);
var
mytime: TDateTime;
SysTime: TsystemTime;
begin
begin
mytime:=Now;
lentdate:=DateToStr(mytime);
GetSystemTime(SysTime);
SysTime.wMonth:=SysTime.wMonth+2;
backdate:=IntToStr(SysTime.wYear)+'-'+IntToStr(SysTime.wMonth)+'-'+IntToStr(SysTime.wDay);

end;
if a=1 then
begin
if edit1.Text=''then
begin
showmessage('請你輸入你的的學號!');
abort;
end;
if edit2.Text=''then
begin
showmessage('請你輸入你要借的書號!');
abort;
end;
dem.dm.conn.Open;
dem.dm.addlent.Append;
dem.dm.addlent.FieldByName('sno').AsString:=edit1.Text;
dem.dm.addlent.FieldByName('bno').AsString:=edit2.Text;
dem.dm.addlent.FieldByName('lentdate').AsString:=lentdate;
dem.dm.addlent.FieldByName('backdate').AsString:=backdate;
dem.dm.addlent.Post;
begin
dem.dm.query3.Close;
dem.dm.query3.SQL.Clear;
sql:='update book set leftno=leftno-1 where bno='''+edit2.Text+'''';
dem.dm.query3.SQL.Add(sql);
dem.dm.query3.ExecSQL;
end;
showmessage('恭喜你借書成功!');
end;
if a=2 then
begin
if edit1.Text=''then
begin
showmessage('請你輸入你的的學號!');
abort;
end;
if edit2.Text=''then
begin
showmessage('請你輸入你要還的書號!');
abort;
end;
begin
dem.dm.query4.Close;
dem.dm.query4.SQL.Clear;
sql:='delete from lent where sno='''+edit1.Text+'''and bno='''+edit2.Text+'''';
dem.dm.query4.SQL.Add(sql);
dem.dm.query4.ExecSQL;
end;
begin
dem.dm.query4.Close;
dem.dm.query4.SQL.Clear;
sql:='update book set leftno=leftno+1 where bno='''+edit2.Text+''' ';
dem.dm.query4.SQL.Add(sql);
dem.dm.query4.ExecSQL;
end;
showmessage('恭喜你還書成功!');
end;


end;

end.